A device of this kind is known from WO 93/12660.
The invention further relates to an extrusion head for coextruding a pasty mass, in particular sausage meat, and a casing surrounding the mass with a filling tube and an extrusion nozzle associated to the filling tube.
Such an extrusion head is known from WO 99/22600.
The device known from WO 93/12660 is in particular appropriate for the manufacture of continuous sausage strands. To this end, an extrusion head which is supplied with a pasty mass, in particular with sausage meat, from a reservoir, is provided. The extrusion head of this known device coextrudes the pasty mass with a casing surrounding the mass in an extruded form. The casing normally consists of collagen, i. e. of protein, which forms an aqueous gel having a high water content.
After the extruded product has exited from the extrusion head, the collagen skin has to be solidified by coagulation. For doing so, the collagen skin is exposed to a coagulation agent, for example a highly concentrated saline solution, for a relatively long period of time.
In the device known from WO 93/12660, the saline solution is contacted with the collagen skin in a solidification means. This solidification means directly joins the extrusion head and consists of a flute which spirally winds downwards starting from the extrusion head. The spiral shape of the solidification flute is to ensure a sufficiently long dwelling time of the extruded product in the flute.
Following this spiral flute, which can have a length of 10 to 15 m, a conventional separate wring-off unit is arranged, in which the extruded product is wrung off in portions. The extruded sausage wrung off in portions is subsequently taken out of the wring-off unit, suspended and conventionally smoked or otherwise further processed.
Due to the spiral design of the solidification flute and due to its considerable length, the production line has large dimensions and accordingly requires excessively space. Moreover, due to the relatively long dwelling time of the extruded product in the solidification flute, the output rate of the known device is relatively low.
The above mentioned disadvantages are partly overcome by the device described in EP 0 932 340 B1.
In this device, the solidification means comprises a belt conveyor instead of a solidification flute, on which the continuous extruded product rests and is drizzled with brine from nozzles along the conveying line. A separate wring-off unit can be provided following the conveying line, which unit takes over the extruded sausage with a sufficiently solidified skin and wrings it off.
It is true that by the use of this conveyor the output rate of this device can be increased. However, the belt conveyor of this solidification means as suggested in WO 93/12660 runs along a spiral path or in serpentines, respectively. Therefore, the device known from EP 0 932 340 B1 also requires a lot of space.
A similar device in which the extruded product is moved underneath spray nozzles on a serpentine-like conveyor with a flexible conveyor belt is known from U.S. Pat. No. 6,024,637. Another device for the manufacture of a strand of a pasty mass with a serpentine-like solidification means is known from EP 0 755 189 B1.
Altogether, in all above described conventional devices, a separate wring-off unit, which is disposed downstream of the spiral solidification line, wrings off the extruded sausage. Therefore, the installation of such devices requires a lot of space.